Corrosion on Portable Fire Extinguishers

Background

An employee was killed when he used a portable fire extinguisher to
put out a small fire. Corrosion on the bottom of the fire extinguisher
was serious enough that the extinguisher case ruptured when it was activated,
and parts struck the fire watch in the chest. A similar incident occurred
in 1988.

The Hazard

This fire extinguisher had a rubber boot or cap to protect the bottom
of the cylinder case. Moisture had seeped in between the rubber and outside
cylinder wall and caused the cylinder to corrode inside the boot. Over
time, this corrosion weakened the cylinder and it ruptured when the internal
CO2 cylinder was activated. Other extinguishers of this type have been
found to have the same type of corrosion underneath the rubber boot.

Recommendation

If your fire extinguishers have rubber or plastic boots or caps and
are located in potentially corrosive environments such as:

Extinguishers stored outside, unprotected from the weather

Extinguishers stored in wet or damp environments

Extinguishers stored near marine facilities or other waterfront buildings,
especially those located near salt water

1. Immediately remove the extinguisher from service and have it inspected
by the vendor or other qualified person.

2. Include inspecting the bottoms of this type of extinguisher as part
of the monthly fire extinguisher inspection.

3. Remind employees that they must stand away from portable fire extinguishers
during re-charging.